The present invention relates to an arrangement for complex diagnosis of internal combustion engines in the course of their operation.
The technical condition of internal combustion engines is at present judged according to conditions of the injection device, of the quality and course of the combustion process, of the level of vibrations and of ultrasonic signals emitted by the main nodal points of the engine. These diagnostic values are now monitored in the course of performance of diagnostic tests on screens of oscilloscopes by means of individual, large and frequently expensive apparatus. The coordination of operation of these frequently rather different units is difficult. The decision about the technical condition of the tested engine has to be made by evaluation of the course or trend of the diagnostic values, as monitored subsquently on the sreeen of the oscilloscope, which technique is not fully reliable, tedious, and demanding on the quality and experience of the technician making the diagnosis, whereby the desired results can be recorded only with difficulty.
There are also complicated automatic diagnostic computer controlled systems with high requirements on the size of memory devices due to the large number of diagnostic values which have to be scanned and due to the necessity of the use of high sampling speeds of the scanned diagnostic dynamic values (50 KHz. and more). Such systems are expensive, they require extensive preparation of individual programs according to the types of engines to be tested, and they can be used only by companies which operate a large number of engines of the same type within a limited space.